1. Technical Field
The following description relates to one or more techniques for a torsion tester, particularly, for a torsion tester configured to conduct both a fatigue test to repeatedly apply to a test body a load in a regularly-used load range over a long period of time and a destructive test to apply to the test body a great load in a breaking load range.
2. Related Art
So far, in order to conduct a fatigue test (a torsion test) for a power transmission component such as a propeller shaft, a hydraulic tester has mostly been used that is configured to generate a repeated load varying at a high frequency. However, in order to attain a great torque and a great displacement required for driving the test body in a destructive test (a torsional destructive test) using the hydraulic tester, a huge hydraulic system needs to be provided. Hence, an electric-motor-type tester is mostly used in the destructive test.
Additionally, in recent years, a low-inertia-type servo motor has been put to practical use that is configured to generate a torque varying at a high frequency, and a servo-motor-type fatigue tester is beginning to be used.